1. Field of the Invention
The present invention relates to a management system in which management is performed from a central unit to remote units.
2. Description of the Related Art
As a data-communications system, as disclosed in Japanese laid-open patent application No. 7-58875, image formation apparatuses such as copying machines installed at places of unspecified users (customers) operate on condition of receiving remote diagnosis from a central management apparatus installed at a service center (base of sales and service etc.), where they are connected by means of communications circuits such as a public network. Then, remote management of the image formation apparatuses by the central management apparatus is performed through the communications circuits.
In such an image formation apparatus management system, each image formation apparatus counts the number of sheets on image formation (summation) according to image formation operation, and each is equipped with a counter which stores the count value. A data-communications apparatus attached to each image formation apparatus periodically (for example, every day at a predetermined time) obtains the above-mentioned count value therefrom as status information. Then, the data-communications apparatus calls the central management apparatus periodically (for example, every month, at a predetermined date and time) via the communications circuit, and then, sends the status information obtained from the image formation apparatus.
In such a management system, in some case according to a user's condition, the central management apparatus may not call the data-communications apparatus, and may only receive call from the user. For example, at the user point, since a call received is not necessarily connected to an extension connected to the data-communications apparatus in a condition in which a pilot number system is applied by using a private branch exchange (henceforth “PBX”), access from the central management apparatus is not permitted. Moreover, since a telephone operator may not understand to which line a call coming from the central management apparatus should be connected in a condition where a telephone call from the outside line to an extension telephone set is made manually by the operator, access from the central management apparatus is not permitted either.
In such a case, in case the telephone number of the central management apparatus is changed, the predetermined date at which the status information is to be summarized for the management is changed, or the like, for example, such a notice cannot be sent to the data-communications apparatus positively from the central management apparatus. Therefore, in order to positively send such a notice, a service person should go to the place of the relevant user, and should manually change the relevant parameters on the data-communications apparatus for the purpose of update.